New Process to Produce Monocrystalline Beta-Silicon Carbide

An innovative process to produce a semiconductor material that will improve the performance of devices ranging from spacecraft to automobile engines has been developed by a 1989 recipient of a fellowship from the Jet Propulsion Laboratory.

Virgil Shields, a doctoral student in Howard University's Materials Science Research Center of Excellence in Washington, D.C., has developed a process to consistently produce high quality monocrystalline beta-silicon carbide at very high bulk growth rates.

Dr. Michael Spencer, the center's director, served as Shields' advisor.

Shields' findings represent an important advance in attempts by researchers to develop new materials that will allow semiconductors and electro-optic circuitry to work faster and more efficiently in extreme temperature and radiation environments.

Because of its properties, silicon carbide is useful for electronic devices on spacecraft that must be able to work in harsh radiation environments or at high temperatures. It would also benefit sensors and electronics on jet engines or automobile engines.

According to Shields, researchers from around the world have attempted to grow large beta-silicon carbide crystals, but had met with limited success. Before his experiment, high-quality crystals in bulk amounts had never been consistently grown.

"We have demonstrated a 300 percent improvement in quality so far," said Shields. "At the same time, producing 100 microns per hour growth rate of this material has engendered a great deal of interest."

The JPL Minority Fellowship Program enables JPL employees from underrepresented minorities to pursue graduate degrees while remaining on the Laboratory staff. Twelve employees have been selected for the program since it was founded in 1989.

The program is sponsored by JPL's Minority Science and Engineering Initiatives Office and funded by NASA's Office of Space Science, Washington, D.C.